Find what’s in the box?
\(3 + \square = 8\)
Answer:
\(3 + \square = 8\)
\(\square = 5\)
Can you do it without guessing?
Subtraction
\(15 - \square = 8\)
\(\square = 7\)
Can you find a way to do it without guessing?
Complete the following
Times tables
\(4 \times \square = 20\)
\(\square = 5\)
Division
\(\square \div 3 = 6\)
\(\square = 18\)
Same problem, different symbol
\(3 \times \square = 15\)
\(3 \times x = 15\)
The letter \(x\) is called a pronumeral
Pronumerals
Letters that stand for numbers:
\(x\), \(y\), \(a\), \(b\), \(c\)…
Now with letters
\(x + 8 = 17\)
\(6 \times y = 30\)
\(25 - a = 11\)
\(b \div 5 = 4\)
Check your work
If \(6 \times y = 30\) and \(y = 5\)
Check: \(6 \times 5 = 30\) ✓
Exit task
On scrap paper, write your name and solve:
\(x + 7 = 15\)
You can do algebra!